235/74 15 tyres??

So i've got some Toyo open countrys in 235/75 15 fitted to what i think are fourtrek alloys.. little bit of poke to them, they look a good size on it i think as it has a 2" spring spacer & damer kit fitted..
My question is will these do any damage to the gearing etc..? Seems to drive fine to me.. I've only just got the jimny as the prev owner fitted every thing... i've trimmed the front bumper as it looked quite close to rubbing on a lock, the front wheel arch at the back looks to be about 2cm from rubbing... since owning i've changed all the wheel bearings, seals and kingpin.. before doing to many miles..
Will i be changing them most weekends with this size tyre? It will mostly be a & b roads with some lite green lanes.

Not knowing what offset the wheels are doesn't help but 235.75 is about the limit of the standard gearing but it will expose any fragility or wear in your clutch.

As Lambert says, you're going to give your clutch a harder time and you'll find it much slower, particularly on motorway climbs.

The offset wheels will cause your wheel bearings to wear out faster.

Every mod has consequences on any car or any type. That's life!

Kirkynut